Why Leaves Change Color and Other Fall Facts


Autumn is a second spring when every leaf is a flower.

-Albert Camus

I like to think of fall from an Alice In Wonderland perspective. That is, autumn is a time when we shrink in proportion to our gardens while the leaves ‘bloom’ above us. And every year nature charts new territory, unveiling color schemes so daring they leave little doubt as to her ability to create designs far superior to our own.


Many people think that cold temperatures cause leaves to change color. But the process is in fact a bit more complex. Although weather can affect the intensity and duration of color, the color itself is a part of each tree’s biology. And just like flowers in a garden, each tree has its own ‘bloom’ period that occurs at different times during the fall season.


Nature’s garden


Leaves change color as a part of their natural life cycle. During the growing season, leaves act as food factories for trees, capturing sunlight to turn carbon dioxide and water into oxygen and sugar. A chemical called chlorophyll, which absorbs light energy, is responsible for making this happen. It is also the reason why most leaves are green.

green leaves in sun

Chlorophyll gives leaves their green color

But in the fall, shorter days and cooler temperatures trigger the leaves to stop their food-making process. As the chlorophyll breaks down, the green color disappears from the leaf surface. Yellow and orange (two colors which until now have been masked by the stronger pigment green) start to become visible. These accessory pigments have a different molecular structure than chlorophyll, and take longer to break down.


Orange-yellow sassafras leaves on Maryland’s Eastern Shore

Some trees like maples, sourwoods and sweet gums, however, start making brand new pigments, producing brilliant shades of red, scarlet and purple with the onset of fall. Often you’ll see these colors mixed in with the orange and yellow accessory pigments.


Maple tree in fall

As the season progresses and temperatures drop further, the cells near the juncture of the leaf and stem weaken and the leaves start falling from the tree. The accessory pigments begin to break down, the leaves dry up, and only a brown color remains. Some plants, like oaks, retain this brown foliage for most of the winter.


Sycamore leaves turn shades of brown


No, weather won’t cause leaves to change color, but it will affect color intensity and duration. This is the reason why each year the landscape looks slightly different. Temperature, amount of sunlight and available water supply all play a role in leaf color.

Lots of sunlight combined with low temperatures, for instance, produces brighter reds but shortens their duration. An early frost, however, spells the end of the show. And drought stress during the summer can result in early dropping of leaves before they have a chance to develop any color at all.


Sugar maple leaf in process of changing color

Surprisingly, a combination of rain and overcast days tend to increase color intensity.


The best and brightest show, however, usually follows a growing season with lots of rain followed by a dry spell.


Looking for a great location to see leaves change color? Click here for America’s 10 Best Places to See Spectacular Fall Foliage. It provides an overview of each area and great places to stay. Happy fall!



Focus On Crocus: Top Varieties To Plant Now

If you’re a fan of early bloomers, then the crocus is the plant for you. For what it lacks in size, it more than makes up for in impression. Resilient and tough, these diminutive flowers will bloom for weeks, even in the harshest of weather. They’re the perfect way to brighten the last gloomy days of winter. 


Crocuses are part of the iris family (Iridaceae), and like irises, grow from bulb-like structures called corms.  There are currently more than 80 known varieties. Of these, the majority bloom in late winter or early spring. But there are a few that flower in late fall.

Measuring in at a wee 3-6 inches, these perennials are indeed tiny. But they’re sneaky. Just when you think they’re dead, they pop up literally overnight. That’s because, unlike daffodils and tulips, their flowers emerge at the same time as the foliage. 

Crocuses open when the sun shines, but close up at night and in rainy weather. There’s a rich pollen inside each flower. This is a boon for pollinators looking for a food source when not much else is available. 

In 1982, Brian Mathew proposed a system that classified crocuses by ‘Series’ including such fancy names as Baytopi, Scardici and Longiflori, to name only a few. Still, those types available for commercial purchase today generally fall into three categories: Species (Snow) crocuses, Giant Dutch crocuses and the Fall-blooming Saffron crocuses.


Species, or Snow crocuses (Crocus chrysanthus) flower in the late winter to early spring, well before the larger Dutch varieties. Measuring around 3-4 inches tall, they’re smaller in size than their Dutch cousins, but they produce more flowers.

Great varieties to try:

Crocus Tommasinianus, also known as the woodland crocus, has pale lavender to reddish-purple goblet-shaped flowers with white throats. The petals appear almost silvery in certain lights. This variety also goes by the name ‘Tommies’.  


Romance produces butter yellow flowers with just a hint of orange. This is a truly tiny variety measuring around 2 to 3 inches.

C. ‘Romance’/Photo: steshs for shutterstock.com

Tricolor  has a bright orange base with violet-blue petals divided by a white band. 

C. ‘Tricolor’/Photo: Erkki Makkonen for shutterstock.com

Blue Pearl has sky blue petals with creamy white insides. If this isn’t the essence of spring, what is?

C. ‘Blue Pearl’/Photo: Erkki Makkonen for shutterstock.com

Ard Schenk has classic white blooms, but unlike other all-white varieties, its golden center and orange anthers make it a standout .

C. ‘Ard Schenk’/Photo: Marinodenisenko for shutterstock.com


Dutch crocuses (Crocus vernus) have large, cup-shaped blooms. At 4-6” tall, they are taller than the snow species. Often sold as ‘mixed’., their cultivars are typically white, lilac or purple and white striped. They bloom in early spring, usually after the snow species.

Great varieties to try:

Flower Record bears large, cup-shaped purple blooms with an orange stamen. This type blooms for about 3 weeks in early spring.

C. ‘Flower Record’/Photo: shutterstock.com

Pickwick is a distinctive striped variety with alternating pale and dark lilac petals and a bright orange style. This variety blooms in early April around the time of the first daffodils.

C. ‘Pickwick’/Photo: steshs for shutterstock.com

Golden Yellow is a a vigorous, clump-forming variety with golden yellow petals. It looks great with purples.

C. ‘Golden Yellow’/Photo: Marinodenisenko for shutterstock.com


Saffron crocuses (Crocus sativas) bloom in the late fall and produce lilac flowers with dark purple veins. Their foliage is barely visible. And yes, you can harvest saffron from the long orange stamens.

C. sativas/Photo: Gts for shutterstock.com

Plant saffron crocuses in the late summer. They like lots of sun and gritty soil with good drainage. The hotter the summer the better.


Dividing your crocuses helps to increase their vigor. Divide the corms every four or five years after the foliage starts to wither. Lift and separate them, discarding the mother corm. Then replant before the ground freezes.

You can plant the corms in sun or part shade. Hardy to zones 3-8, they need a cold winter to bloom properly. Never plant crocuses in wet or soggy soil, which can cause the corms to rot.

As with all spring flowering bulbs, it’s important to leave the foliage on until it yellows. The plants store their energy in the leaves for the following year. 


The Truth About Recycling Plastic Pots

Have you ever wondered what happens to all those plastic pots once we’re done with them? I was under the false impression that most were recycled. As it turns out, a large percentage of them join other single-use plastics in landfills. That’s according to Jean Ponzi, Green Resources Manager in the sustainability division of the Missouri Botanical Garden.

Years ago, Ponzi asked herself the very same question. What followed was the launch of the largest plastic pot recycling program of its kind. Since 1998, the Missouri Botanical Garden’s Plastic Pot Recycling Program (MOBOT) has saved over 300 tons of plastic from reaching area landfills.

The problem is that it has only made a small dent in the problem.


According to the EPA, in 2017, the U.S. produced 35.4 million tons of plastic. Of that, about 26.8 million tons, or 76 percent, went to landfills. This mean that, of all the plastic produced, only 8.5 percent was recycled.

Until recently, China bought most of our plastic waste and recycled it into new products. But in 2017, the country went from purchasing 60 percent of our plastic to 10 percent, drastically increasing the amount sent to our U.S. dumping grounds. This amount is now expected to double over the next two decades.


There’s no doubt that the black plastic pot changed the horticultural industry. It was easy to transport, lightweight and flexible. Plastic, in fact, was a game-changer for a wide range of household products. Containers are today one of the major products the plastic industry produces.

black plastic pots

Yet with all the convenience plastic containers represent, there is currently no national infrastructure for processing our plastic waste. And when it comes to black plastic pots, there’s an added dimension. Since they’re dyed with carbon inks that can’t easily be broken down, black plastic pots are non-recyclable. That makes them a single-use plastic, which takes around 450 years to break down.

Enter Marie Chieppo, Principal at EcoPlants Plans, and participant in the MOBOT program. She decided to dig deeper into what goes into recycling plastic pots and why the process is so difficult. What she discovered is revolutionary for we gardeners.


According to Chieppo, where it comes to recycling, all plastic pots pose a problem. Since they are derived from fossil fuel hydrocarbons, they are non-biodegradable. Further, in order to be able to be recycled, they must be:

DECONTAMINATED – that means all soil and debris must be removed from the container. Anything that stays in the pot wreaks havoc on recycling facilities by dulling the knives of the grinding machinery.

SEPARATED BY COLOR AND DENSITY – each of which can have an effect on how a pot can be recycled.

STACKED – this can be a nightmare because they’re all configured differently. Plus they take up a lot of room in the recycling bin.

ABLE TO BE RECYCLED – some can be reused, but most cannot (as in the case of black plastic pots), says Chieppo. For example, you can’t mix polymer types. That’s because there are three primary resins used in the manufacture of horticultural pots. And each is processed differently. 

roll-off container

The net result is that recycling plastic pots is a very expense and labor-intensive process.

‘The sad truth is that 95-98 percent of plastic horticultural pots end up in the landfill,’ says Chieppo.


So what can we gardeners do to mitigate the problem? Until a better plastic is developed, we can try our best to recycle. To do so, we need to educate ourselves first as to the process. For instance, we must never mix horticultural products with other plastics. 

Instead, we must first wash and disinfect our used plastic pots to kill any plant pathogens. Then we can put green, blue or red plastic pots out for recycling. But black plastic pots and trays must be put in the trash.

Or, you can take your used plastic pots (non-black) to places like Home Depot and Lowes, both of which have garden pot recycling programs.


Can anyone unseat plastic? Several manufacturers are trying. Some are now producing new pots out of ‘Bioplastics’ (a hybrid starches combined with petroleum). Other companies are manufacturing compostable pots, plantable pots and pots made from cow manure among other things. All of these alternatives can produce and grow plants as well as plastic ones.

Plantable pots are an option growing in popularity

But before we can begin making a dent in our plastics waste problem, companies will need to mass produce them. This process has yet to be developed. For now, the best way forward is to educate ourselves as to viable alternatives to plastic pots and to recycle the ones we do use appropriately. 

‘It’s not an Either/Or’, says Chieppo.



A Beginner’s Guide To 13 Types of Daffodils

At the end of summer, daffodils are rarely top-of-mind. But this is precisely the time when you should be ordering them. And this is especially true for the more sought-after, unusual varieties. Why stick with yellow trumpets when daffodils come in so many other colors, shapes and sizes? See below if one or more of these different types of daffodils wouldn’t be the perfect fit for your 2021 spring garden. 


The choices are seemingly endless. Depending on who you talk to, there are currently between 40 and 200 different daffodil species and over 32,000 registered cultivars. To keep them all organized, horticulturalists split them into 13 divisions. Known as the Official Classification System, it categorizes daffodils based on the size and shape of their cups as compared to their petals.

Here’s a rundown of the divisions and links to some of the standout varieties in each one. 


Characterized by large blooms and only one flower to a stem, these cultivars have trumpets that are as long or longer than their petals. Trumpet daffodils are some of the earliest to bloom, and come in a wide variety of shapes and colors. Try Mount Hood, King Alfred and 4U2.

Trumpet daffodil ‘King Alfred’


These cultivars have cups that are more than one third, but less than equal to the length of their petals. Each stem bears a single flower. Large-cupped daffodils come in a wide range of colors and have flat, ruffled or trumpet-like shapes. Great varieties include: Salome, Ice Follies and the exquisite, soft yellow Day Dream.

Large-cupped daffodil ‘Salome’


These daffodils have cups that are not more than one third the length of their petals. Each stem carries one medium-sized flower. Popular selections include the exquisitely-shaped Eleanor Auchincloss, Ringtone and Barrett Browning.

Small-cupped daffodil ‘Barrett Browning’


Not everyone’s a fan of these unusually-shaped flowers with their frilly rows of petals that resemble carnations. Nevertheless, these types of daffodils have a sweet fragrance and look great under flowering shrubs and trees. Each produces one or more blooms to a stem. Try pink and white Replete, tropical-colored Tahiti or soft pink Angélique.

Double daffodil ‘Tahiti’


Tiny and low-growing, these daffodils have petals that flare back and droop downwards like columbines. Triandrus daffodils prefer wetter conditions and produce two or more pendent flowers to a stem. Great varieties include the dainty white Thalia, soft yellow ‘Angel’s Breath‘ and bright yellow Hawera.

Triandrus daffodil ‘Thalia’


Cyclamineus daffodils have smaller-sized trumpets and petals that flare back from the cup. Prized for their early flowering and diminutive size, they’re perfect for naturalizing in large masses. Great varieties include: Wisley, Peeping Tom and February Gold.

Cylcamineus daffodil ‘February Gold’


Instead of the flat leaves found in most daffodils, jonquils have dark green, tube-shaped leaves that resemble rushes. Strongly fragrant, they feature three or more small blooms to a stem. Although they are traditionally yellow, jonquils are also now available in white/yellow combinations. Great for naturalizing. Try Pueblo or Bell Song.

Yellow jonquil daffodils


Producing fragrant clusters of up to 20 flowers to a stem, tazetta daffodils are prized for their strong scent and heavy flower bearing. Great varieties include Geranium, Grand Primo and one of my personal favorites, Minnow.

Tazetta daffodil ‘Minnow’


It doesn’t get cuter than this! Also known as Pheasant’s Eye, Poet’s daffodils have very shallow, red-rimmed cups that look like an eye, especially when silhouetted against their bright white petals. Each has just one flower to a stem. Poeticus are one of the latest types of daffodils to flower. Great varieties include: Actaea and Recurvus.

White Poet’s daffodil


Also known as Petticoat daffodils for their lampshade-shaped cups, bulbocodiums grow to just 4 to 6 inches. The smallest of all the narcissus, the species is unusual in that its trumpet is exceptionally large in relation to its petals. Check out Yellow Hoop and Spoirot.

Yellow ‘Petticoat’ daffodils


Also called Butterfly daffodil, split-cupped daffodils have cups that splay out, which makes them appear as if they have another ring of petals. 

Look for Apricot Whirl, Lemon Beauty and tiny coral-pink Shrike.

Split-cupped daffodil


This division Includes all those daffodils that don’t fall into the above classifications. Many are variants or hybrids of natural species.

Mesa Verde daffodil at the RHS SHow

Mesa Verde, a new cultivar developed in California by Bob Spott/Photo: RHS Flower Show


Often left off the list, according to The Daffodil Society this division is nonetheless a part of the official daffodil classification system. It includes all the wild daffodils.


On the East Coast, we plant our spring bulbs in November, once nighttime temperatures have fallen to around 45 to 50 degrees F. So hold on to your new purchases until at least late October. This is approximately six weeks before the first hard frost. 

Plant your bulbs with the pointy end up and the flat end down. And make sure the hole is twice as deep as the size of the bulb. Back fill with soil and water well. 

Once planted, all daffodil varieties are maintenance free and will naturalize year after year. Deer won’t touch them (due to some toxic properties.) Just make sure to respect your bulb’s requirements. They’ll flower best in full sun, but will tolerate part shade. And in my experience, they do fine in deciduous woodlands.

While there are many theories on when to remove the leaves, I ascribe to the one that advocates leaving the leaves on for about 6 weeks after blooms until they yellow. This allows the plant to absorb energy from sunlight, which it redirects back down into the bulb to feed next year’s flowers.

Bulbs coming up too early? Check out my post, What To Do If Your Spring Bulbs Come Up Too Early.


Top Annuals for the All-Season Cutting Garden

Annuals for the cutting garden/Photo: Julie Hove Anderson Photography

As a landscape designer, I’m well versed in perennials and the kind of annuals you buy from a nursery. But when it comes to growing annuals from seeds, my experience centers mainly on zinnias. So recently, I was delighted to attend a webinar given by ButterBee Farm owner Laura Beth Resnick on the top annuals she grows for her cutting gardens.

Located in Pikesville, Maryland, ButterBee Farm specializes in growing flowers organically for florists, weddings, and flower lovers across the Maryland and DC areas. Established in 2013, the farm has since grown to encompass just around 5 acres. In addition to signature perennials such as peonies and ranunculus, Resnick grows ornamental foliage and thousands of annuals, both in the field and in heated and unheated greenhouses.

The goal, says Resnick, is to provide her customers with flowers and foliage all year-round.

One of ButterBee Farm’s cutting gardens/Photo: Julie Hove Anderson Photography


There’s so much to learn from Resnick and her wealth of plant knowledge. But today’s focus was on annuals for cutting. And annuals often have quite different needs from those of perennials. For example, while there are perennials that are built for sun and others for shade, annuals need at least 8 hours of sun a day. If your site is shady, it’s not the best location for a cutting garden.

Annuals like zinnias grow best in full sun/Photo: Here By Design

According to Resnick, if you want to successfully grow annuals for cutting, you need three things:

And lots of sun can mean high water needs. Cutting gardens need constant monitoring to make sure thirsty plants are getting enough moisture. Unlike perennials, annuals are shallow-rooted, meaning their roots are located close to the soil surface. They dry out fast once the surface water has evaporated.

Annuals are shallow-rooted

But even with lots of sun and diligent watering, your cutting garden can sometimes under-perform if you don’t know what kind of soil you’re dealing with. Resnick stresses the importance of getting a soil test before planting.

“It’s kind of like getting your blood work done,” she said.

Soil pH, for example, can have a huge effect on plants. And it can determine what kinds of minerals are available.

Good soil is essential to the life of a garden/Photo: shutterstock.com

Luckily, getting a soil test is easier than ever – just dig up some samples, put them in a plastic bag and ship them off to a soil analysis center. You can find them through university extension offices, Agro Lab, or my personal favorite, University of Delaware. They email you the results complete with recommendations for how to improve your soil for what you want to grow. 


Unlike perennials, which come up on schedule year after year, if you’re growing annuals from seeds, it takes some planning. And if you’re growing annuals for a cutting garden, it’s best to start backward. That means, start by determining when you want to have things blooming and then work backward to when you have to plant.

Days to Flower is a key term to remember when purchasing a seed packet. It refers to the amount of days it takes from when the seed germinates until the day it’s ready to be harvested. Some packets won’t tell you, so you may have to do a google search. Johnny’s Selected Seeds, though, does. And Resnick says it’s a good quick stop.

Below is an example of a chart Resnick uses to determine when to plant June annuals for her cutting garden. 


Finally, even the most seasoned of gardeners have failures. No two seasons are alike. Taking notes on what happens each year is really helpful. Resnick stresses creating a planting calendar and referring back to it when making your selections.

Most importantly, when choosing annuals for cutting, strive for diversity. Not everything you try is going to work out. Plant a bunch of different things that bloom in spring, summer and fall. It’s a good way to hedge your bets.

Laura Beth Resnick, Owner ButterBee Farm/Photo: Julie Hove Anderson Photography


Below are Resnick’s top annuals for the cutting garden, organized by season.


Bachelor’s Button, a cool-season annual/Photo credit: shutterstock.com

Larkspur– Resnick direct seeds annual larkspur (which is different from the perennial) in the fall between Sept 15 and October 15. Favorite varieties are Early Grey and the QIS series.

Snapdragon– She loves Chantilly and Madame Butterfly, which she plants in the fall and Rocket and Potomac, which she plants in the spring. She pinches her plants to encourage branching.

Bachelor’s Button (Blue Cornflower)- She direct seeds in the fall. Try Black or Blue Magic. These flowers love to re-seed.

Feverfew– If you plant in the fall, feverfew will bloom earlier in the spring. If you plant in the spring, it will bloom later. Resnick likes the single-flowered Virgo variety. 

Scabiosa– She plants in the fall and spring. Her favorite varieties include Ping Pong, Black Knight, and the creamy apricot Fata Morgana.


Deep red sunflower variety ‘Moulin Rouge’/Photo: shutterstock.com

Sunflowers–  Resnick plants sunflower seeds every week in summer. ‘You can plant them every week and you’ll have them every week,’ she said. She plants the seeds close together for smaller flower heads, which look better in vases. Favorite varieties include Moulin Rouge (above) and the Procut Series.

Zinnias– She plants every 3 weeks for continuous bloom through fall. Aztec, Persian Carpet (also called Mexican zinnia), Queen Red or Queen Orange are her favorites.

Strawflower- ‘This is what is called ‘everlasting,’ said Resnick. ‘When it blooms, it’s already dried.’ She plants in the spring. Good varieties include Apricot, Purple-red and Silvery Rose

Cosmos- She plants seeds every 3 weeks in summer and pinches plant tips to promote branching. Resnick prefers the Double Click series over the single flower. It is a little more resilient in the heat. 

Celosia– Resnick recommends planting every 2 weeks, from summer to fall. She recommends the Sunday and Chief series. If your budget allows, the Bombay series has the most unusual colors. 


Pink gomphrena/Photo: shutterstock.com

Hairy Balls– These are excellent focal flowers, albeit a little strange. They are part of the milkweed family, whose flowers are the only flowers monarch butterflies will eat. Plant seeds in spring or early summer but be mindful of the sap. If you get it in your eyes, it can send you to the hospital.

Marigolds (Tagetes)- Make sure to purchase the cutting variety, not the bedding one, which is short. Resnick plants seeds from summer to fall. She likes the Jedi series, Tagetes erecta, known to be the most disease tolerant and tallest of the cutflower series.

Gomphrena– She plants from summer to fall. Check out the QIS series and Audray series.

Ornamental Kale- She plants from late summer to fall. There are so many different, amazing varieties featuring unusual colors and foliage. Resnick likes the tall variety, Crane, and its feather-leafed version ‘Feather’. Plant in late summer to fall.

Dahlias– Okay, these aren’t seeds, but they are stalwarts of the late summer garden. Plant in early summer. In Maryland, we plant our tubers in June. Resnick loves Cornel Bronze, Nathalie g, Cafe au Lait, and Jowie Linda. Plant 15” apart.

Ready to plant? I am. It’s late July in Maryland, but it’s clear from Resnick’s chart that there is still plenty of time to sow annual seeds. Make sure to check your Plant Hardiness Zone, though. Resnick’s charts are built for her area of Maryland, which is zone 7a – 7b. All links are for informational purposes only, and are not paid links. 

Looking for more great ideas? Check out ButterBee Farm’s instagram at @butterbee_farm. 


Daylily Care: How To Extend The Blooming Season

Daylilies are called daylilies for a reason. Each flower lasts for just one day. But that doesn’t mean you can’t enjoy more blooms, more often. All it takes is a little gardening know-how, and you can trick your plant into extending its blooming season. Continue reading

Finding Your Center on the Labyrinth Path

Sometimes life can seem like a maze, full of twists and turns and lots of dead ends. It’s not always clear how to approach the center. But for those willing to walk its cousin, the labyrinth, there can be true transformation. Some say the process ultimately leads to insights into the circuitous path of life itself. Continue reading

Eating Mushrooms: The Health Benefits Of Fungi

lingzi cover

I’ve been doing mushrooms for years. And it’s changed my life. My mushroom of choice is reishi,  which I drink in tea-form every morning. But reishi isn’t the only fungi with the potential for improving human health. Many mushrooms, molds and lichens are loaded with immune-enhancing, antimicrobial and antioxidant properties, making them some of the most potent forms of natural medicine on earth. Continue reading

Identify Plants In A Snap With These 6 Top Apps

 What's That Flower app

Now that we’re all spending more time at home, it doesn’t hurt to know what’s blooming. And finding the answer is easier than ever with one of the dozens of plant identification apps available. But which ones work best and provide the fastest, most reliable material? I decided to do a comparison. Continue reading

Gardening For Troubled Times

‘It was an uncertain spring.’ – Virginia Wolf, The Years

In times of trouble, I often turn to Voltaire’s Candide to help put things in perspective. In this classic satire, Candide and his companions undergo unspeakable hardships only to find themselves in the end alone, together. Faced with a new normal, Candide arrives at the only sensible conclusion.  “We must cultivate our garden,” he says. Continue reading